Place the milk, sugar, cinnamon, and
salt in a large saucepan over medium heat. Cook, stirring
constantly, until the chocolate has melted completely. Add chestnut
puree and cook, stirring constantly, until the puree is completely
incorporated. Stir in the liquors, if desired. Ladle into mugs, top
with whipped cream, and a chestnut piece, if desired, and
serve.